"380 MRS. E. W. SEXTON ON A [AW- 28, 



Male (PL XIV. fig. 14). The apex of the front part of the trunk 

 is more spatulate than that of the female. The proportions of 

 the joints of the pcdj) vary a little also, the 3rcl joint being slightly 

 longer than the 2nd, which is more elongate in form than that 

 of the female. The row of bristles on the 2nd joint commences 

 lower down the margin ; in the right mandible they number 34 

 on the 2nd joint, and 27 on the 3rd ; the left mandible having 

 31 on the 2nd, and 26 on the 3rd. The numbers appear very 

 variable. In the Mediterranean specimen examined they were : 

 right mandible 37 and 26 respectively ; and on the left 30 

 and 25. 



First Maxilla (PI. XY. figs. 1 & 2). — The otiter plate is elon- 

 gate, with five strong claws apically, four much curved, and 

 serrated (see fig. 1, detail). The plate is contracted below the 

 apex and again at the insertion of the palp. The small pellucid 

 inner plate is of very delicate structure, unarmed. The jxdp is 

 bi-articulate, minute, set in a hollow and united along its length 

 to the inner surface of this hollow, the laminar leaf-like second 

 joint being twice the length and breadth of the first. 



There is practically no difierence between the sexes, except 

 that the first maxilla of the male is longer than that of the female 

 and the apical claws are longer. 



Second Maxilla (PI. XY. fig. 3). — Slightly larger in male 

 than in female. Inner p)late small, tipped with one setule ; outer 

 ■plate broad and rounded distally, hollowed underneath, with three 

 setules on the apical margin and one on the inner side. 



Maxillipeds (PI. XY. figs. 4 & 5). — Female. The basal joints 

 deeply curved ; the 2nd joint of the one maxilliped fused with 

 that of the other for nearly three quarters of its length. Inner 

 plates faii'ly lai-ge, nai-rowing apically, unarmed. Outer plates 

 extending beyond the distal margin of the first joint of the palp ; 

 large, unarmed except for one or two microscopic setules. 



The 1st joint of the palp is large and broad; the 2nd short, 

 widening a little distally, with one seta at each angle ; the 3rd is 

 the largest of all (measured along the outer margin), lightly 

 curved, with seven transverse rows of strong bristles on its under 

 surface (see detail, fig. 5), and two setse. on the inner distal 

 margin. Distally the under surface of the joint is covered with 

 a spinose armature similar to thst of the mandibular palp. The 

 4th joint is subequal in length to the 2nd, narrow and unarmed. 



Male. The basal portion and plates are the same as in the 

 female, but the proportions of the joints of the palp vary. 



The 1st joint is the longest ; the 2nd the shortest, with one 

 seta on its inner angle and two clusters of the long bristles distally 

 on the outer margin ; the 3rd joint is slightly shorter than the 

 1st, curved, densely setose on its under surface, with about ten 

 transverse rows of long bristles ; the 4th joint is subequal to it 

 in length, biit onlj'' half its width and unarmed. 



First Gnathopod (PI. XY. figs. 6, 7, & 8) very powerful, with 

 the chitinous margins of extraordinary thickness, and longi- 



